1. Field of the Invention
This invention relates to a gasoline-soluble reaction product, to a concentrate comprising the reaction product dissolved in a hydrocarbon solvent, and to a haze-free, deposit-resistant and ORI-inhibited motor fuel composition comprising the reaction product. More particularly, this invention relates to: (i) the reaction product of a dibasic acid anhydride, a novel diamine containing block copolymers with polyoxyalkylene backbones, and a hydrocarbyl polyamine; (ii) a concentrate comprising the reaction product dissolved in a hydrocarbon solvent; and (iii) a haze-free motor fuel composition comprising the reaction product. Motor fuel compositions comprising the reaction product of the instant invention are haze-free, ORI-inhibited, and have a reduced tendency to form deposits.
2. Information Disclosure Statement
Combustion of a hydrocarbonaceous motor fuel in an internal combustion engine generally results in the formation and accumulation of carbon deposits on various parts of the combustion chamber as well as on the fuel intake and exhaust systems of the engine. The presence of deposits in the combustion chamber seriously reduces the operating efficiency of the engine. First, deposit accumulation within the combustion chamber inhibits heat transfer between the chamber and the engine cooling system. This leads to higher temperatures within the combustion chamber, resulting in increases in the end gas temperature of the incoming charge. Consequently, end gas auto-ignition occurs, which causes engine knock. In addition, the accumulation of deposits within the combustion chamber reduces the volume of the combustion zone, causing a higher than design compression ratio in the engine. This, in turn, also results in serious engine knocking. A knocking engine does not effectively utilize the energy of combustion. Moreover, a prolonged period of engine knocking will cause stress fatigue and wear in vital parts of the engine. The above-described phenomenon is characteristic of gasoline powered internal combustion engines. It is usually overcome by employing a higher octane gasoline for powering the engine, and hence has become known as the engine octane requirement increase (ORI) phenomenon. It would therefore be highly advantageous if engine ORI could be substantially reduced or eliminated by preventing deposit formation in the combustion chamber of the engine.
An additional problem common to internal combustion engines relates to the accumulation of deposits in the carburetor which tend to restrict the flow of air through the carburetor at idle and at low speed, resulting in an overrich fuel mixture. This condition also promotes incomplete fuel combustion and leads to rough engine idling and engine stalling. Excessive hydrocarbon and carbon monoxide exhaust emissions are also produced under these conditions. It would therefore be desirable from the standpoint of engine operability and overall air quality to provide a motor fuel composition which minimizes or overcomes the above-described problems.
Deposit-inhibiting additives for use in motor fuel compositions are well known in the art. For example:
Co-assigned U.S. patent application Ser. No. 000,253, filed Jan. 2, 1987, (D#78,650) (Sung et al.) discloses a novel polyoxyalkylene diamine compound of the formula: ##STR1## where c has a value from about 5-150, b+d has a value from about 5-150, and a+e has a value from about 2-12. Motor fuel compositions comprising the novel polyoxyalkylene diamine, alone or in combination with a polymer/copolymer additive are also disclosed.
Co-assigned U.S. Pat. No. 4,689,051 (Sung) discloses an additive composition useful in improving the storage stability of middle distillate fuel oils, the additive prepared by reacting (i) a hydrocarbon-substituted mono primary amine or a hydrocarbon-substituted mono primary ether amine, (ii) a dibasic acid anhydride, and (iii) an N-alkyl alkylene diamine.
Co-assigned U.S. Pat. No. 4,581,040 (Sung et al.) teaches the use of a reaction product as a deposit inhibitor additive in fuel compositions. The reaction product taught is a condensate product of the process comprising: (i) reacting a dibasic acid anhydride with a polyoxyisopropylenediamine thereby forming a maleamic acid; (ii) reacting the maleamic acid with a polyalkylene polyamine, thereby forming a condensate product; and (iii) recovering the condensate product.
Co-assigned U.S. Pat. No. 4,659,336 (Sung et al.) discloses the use of the mixture of: (i) the reaction product of maleic anhydride, a polyether polyamine containing oxyethylene and oxypropylene ether moieties, and a hydrocarbyl polyamine; and (ii) a polyolefin polymer/copolymer as an additive in motor fuel compositions to reduce engine ORI.
Co-assigned U.S. Pat. No. 4,659,337 (Sung et al.) discloses the use of the reaction product of maleic anhydride, a polyether polyamine containing oxyethylene and oxypropylene ether moieties, and a hydrocarbyl polyamine in a gasoline motor fuel to reduce engine ORI and provide carburetor detergency.
Co-assigned U.S. Pat. No. 4,643,738 (Sung et al.) discloses a motor fuel additive useful in reducing combustion chamber deposits, the additive prepared by reacting a dibasic acid anhydride, a polyoxyisopropylene diamine, and an N-alkyl-alkylene diamine.
Co-assigned U.S. Pat. No. 4,643,737 (Sung et al.) discloses a motor fuel additive useful in reducing combustion chamber deposits, the additive prepared by reacting maleic anhydride, an alpha-hydroxy omega-hydroxy-poly(oxyethylene) poly(oxypropylene) poly(oxyethylene) block copolymer, and an N-alkylalkylene diamine.
Co-assigned U.S. Pat. No. 4,631,069 (Sung) discloses a wear-inhibiting additive for use in alcohol fuel compositions, the additive prepared by reacting a polyoxyisopropylene diamine, a dibasic acid anhydride, and an N-alkyl-alkylene diamine.
U.S. Pat. No. 4,604,103 (Campbell) discloses a motor fuel deposit control additive for use in internal combustion engines which maintains cleanliness of the engine intake system without contributing to combustion chamber deposits or engine octane requirement increase (ORI). The additive disclosed is a hydrocarbyl polyoxyalkylene polyamine ethane of molecular weight range 300-2500 having the formula ##STR2## where R is a hydrocarbyl radical of from 1 to about 30 carbon atoms; R' is selected from methyl and ethyl; x is an integer from 5 to 30; and R" and R'" are independently selected from hydrogen and --(CH.sub.2 CH.sub.2 NH-).sub.y H where y is an integer from 0-5.
Conventional additives may cause hazing of the motor fuel. Hazy motor fuels are unacceptable by the public since they may indicate a problem with the fuel, such as the presence of undesired contaminants. It would therefore be desirable to provide a haze-free motor fuel composition which is deposit-resistant and ORI-inhibited.
It is one object of this invention to provide a gasoline-soluble reaction product additive for use in motor fuel compositions. It is another object of this invention to provide a concentrate composition comprising the reaction product additive dissolved in a hydrocarbon solvent. It is yet another object of this invention to provide a haze-free, deposit-resistant and ORI-inhibited motor fuel composition comprising the reaction product.
It is one advantage of this invention that motor fuel compositions of the instant invention are haze-free, ORI-inhibited, and deposit-resistant. It is another advantage of this invention that the reaction product additive of the instant invention is soluble in gasoline and similar motor fuel compositions, and therefore requires no admixing with a solvent prior to introduction into a base motor fuel composition.
It is one feature of this invention that the reaction product additive is gasoline soluble. It is another feature of this invention that the motor fuel composition is haze-free, ORI-inhibited, and deposit-resistant.